Ammunition launcher firing mechanism with breech closure means



S. D. SILSBY AMMUNITION LAUNCHER FIRING MECHANISM WITH BREECH CLOSURE MEANS Filed June 13, 1961 3 Sheets-Sheet 1 o INVENTOR. 0 SinnLay D Eilijy 4 Rama w aaQ wf S. sBY

Nov. 5 68 AMMUNITION LAUNCHER FIRING MECHANISM WITH BREECH CLOSURE MEANS Filed June 13, 1961 3 Sheets eet 2 INVENTOR' Single) ll E-bi,

Nov. 5, 1968 s. D. SILSBY 3,408,761

AMMUNITION LAUNCHER FIRING MECHANISM WITH BREECH CLOSURE MEANS Filed June 13, 1961 3 Sheets-Sheet 3 8o INVENTOR.

Elunleyfl-5fliy BY Unitd S atent 3,408,761 AMMUNITION LAUNCHER FIRING MECHANISM WITH BREECH CLOSURE MEANS Stanley D. Silsby, Granby, Mass, assignor to the United States of America as represented by the Secretary of the Army Filed June 13, 1961, Ser. No. 116,886 7 Claims. (Cl. 421) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to firearms and more particularly to ammunition launchers which are attachable to a firearm barrel.

It is one object of this invention to provide for attachment to a firearm barrel an ammunition launcher which is distinguished for simplicity of design and ruggedness of construction.

It is another object of this invention to provide such a launcher wherein the breechblock is actuatable between an open and a closed position and is releasably locked in the closed position by the firing mechanism.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

FIG. 1 is a side view of the ammunition launcher mounted on a firearm barrel and longitudinally sectioned to show the arrangement of the parts when the firing mechanism is in the cocked position;

FIG. 2 is a bottom view of the launcher;

FIG. 3 is a side view of the launcher with the breechblock in the open position and the firing pin pulled back to the unlocking position;

FIG. 4 is a view of the rear end of the launcher with the breechblock in the closed position;

FIG. 5 is a view taken along line 5-5 of FIG. 1;

FIG. 6 is a fragmentary, longitudinally cross-sectioned view of the rear end of the launcher with the breechblock displaced adjacent the closed position and the firing pin in camming contact with the locking lug;

FIG. 7 is an exploded, perspective view of the firing pin and casing; and

FIG. 8 is a fragmentary side view of the rear end of the launcher showing an alternate means for joining the breechblock to the casing and mounting the breechblock in the breech housing.

Shown in the figures is a firearm barrel 12 to which there is replaceably mounted a launcher 14 for a grenade 16 which is contained in a case 20 with a radial rim 22 around the base thereof and which is energized for flight by a propellant 24 initiatable by a primer 26 thereby forming a cuplike round of ammunition.

Launcher 14 includes a tube 28 having an inside diameter similar to the outside diameter of case 20 so that case 20 may be inserted into the tube from the rear end thereof. Contact of rim 22 with the rear end of tube 28 positions case 20 therein for discharge. The rear end of tube 28 is enlarged to form a breech housing 30 of rectangular cross-section. The base of case 20 is supported for discharge by a breechblock 32 which is slidingly mounted in breech housing 30, as hereinafter described, for vertical displacement between an open position, for loading the case in tube 28, and a closed position for supporting the base of the case for discharge. Breechblock 32 is displaceable between the open and closed positions and is releasably locked in the closed position by a firing mechanism 34 as hereinafter described.

FIGS. l-7 illustrate one way in which breechblock 32 may be mounted in breech housing 30 and disposed for operational cooperation with firing mechanism 34. As shown in such figures, breechblock 32 is substantially of rectangular configuration and is slidingly received by a vertical channel 36 in breech housing 30. A pair of vertically disposed flanges 38 on the sides of breechblock 32 are slidingly received by mating grooves 40 in breech housing 30 to guide the breechblock for vertical displacement between the open and closed positions.

Firing mechanism 34 includes a casing 42 of rectangular cross-section. The front end of casing 42 is bifurcated by a vertical slot 44 which receives a lug 46 depending from the front portion of tube 28 and which forms a pair of tines 48. A pin 50 extends laterally through lug 46 so as to project on opposite sides therefrom and such projecting ends are respectively received by slots 52 which extend rearwardly into tines 48 thereby forming a fulcrum for the pivotal movement of casing 42. The rear end of casing 42 is received by a vertical recess 54 which extends upwardly into breechblock 32 from the bottom thereof. A pair of axles 56 extend laterally through breechblock 32 and casing 42 to pivotally connect the casing thereto. The connection of casing 42 with breechblock 32 maintains slots 52 in engagement with pin 50.

Casing 42 is also provided with a longitudinal bore 60 which slidingly mounts a firing pin 62. Firing pin 62 includes a shaft 64 having an outside diameter similar to the diameter of bore 60 so as to be slidable therein. Extending from the front end of shaft 64 is a rod 66 of smaller diameter and such rod is fixed to the shaft as by pin means. A cylindrical button 68 is fixed to the front end of rod 66 and a collar 70 having the same diameter as shaft 64 is slidingly mounted on the rod. A compressible coil spring 72 is coiled around rod 66 between collar 70 and button 68 and the collar is anchored to casing 42 by a U-shaped lock 74 which is insertable therein to engage with an annular groove 76 around the outside perimeter of such collar whereby, firing pin 62 is biased forwardly by spring 72 to a striking position.

Fixed to the rear end of shaft 64 is an inverted T-shaped support 78 having a laterally disposed crosspiece 80 and a leg 82 which extends vertically upward intermediate the ends thereof. Fixed to the top end of leg 82 is a striker 84 which extends forwardly for projection through a mating orifice 86 in breechblock 32 to strike primer 26 of case 20 when firing pin 62 is released to the firing position. An inverted U-shaped guard 88 is integrally formed on the rear end of breechblock 32 to protectingly surround leg 82 and striker 84 and also prevent angular displacement of firing pin 62. Provided on each end of crosspiece 80 is a vertically disposed finger-gripping plate 90 which is angularly arranged relative to the central vertical plane of launcher 14 to facilitate the application of manual force to firing pin 62 for rearward displacement thereof against the bias of spring 72.

Firing pin 62 is held cocked, after being pulled rearwardly, by a sear device 92 which is similar to that disclosed by Charles F. Packard and Stanley D. Silsby in their copending application for Firing Mechanism for a Spotting Rifle, Ser. No. 82,659, filed Jan. 13, 1961. Sear device 92 includes a pivotal trigger 94 and a pivotal safety lever 96 which are laterally disposed so they may be manually squeezed together between the thumb and forefinger and which are biased apart to inoperative positions by a common spring 98. Trigger 94 and safety lever 96 are operationally arranged so that the trigger is actuatable only when the trigger and safety lever are simultaneously squeezed together, whereby because of common spring 98, equal force is applied to opposite sides of launcher 14 so that the sighting alignment of the launcher is not disturbed when the trigger is actuated. Trigger 94 includes an integral sear portion 100 at the rear end and such sear portion is disposed for releasable contact with button 68 when firing pin 62 is in the cocked position to block forward displacement thereof.

Breechblock 32 is releasably locked in the closed position by the operational cooperation of firing pin 62 with a locking lug 102 which depends from the bottom of tube 28 adjacent'the rear end thereof and which is receivable by a mating opening 104 that extends vertically through casing 42. Locking lug 102 is provided with a longitudinal aperture 106 having the same diameter as shaft 64 which is slidingly received thereby when breechblock 32 is in the closed position, whereby casing 42 is blocked against pivotal displacement and the breechblock is locked thereby in the' closed position. To permit displacement of breechblock 32 from and to the closed position, shaft '64 is provided with a pair of laterally opposed segmental cuts 110 which form a reduced section 112 having a pair of vertical, parallelly disposed flats 114. Aperture 106 is interrupted by a vertical slot 118 which extends upwardly from the bottom of locking lug 102 and has a width equal to the distance between flats 114 to permit the passage of reduced section 112 therethrough when aligned therewith. Reduced section 112 is located on shaft 64 so as to align with slot 118 when firing pin 62 is pulled rearwardly past the cocked position to an unlocking position. The rear sides of the segmental cuts 110 incline upwardly and rearwardly as noted at 120 for camming contact with a chamfer 122 on the bottom rear edge of locking lug 102, whereby firing pin 62 is actuated rearwardly from the cocked position to the unlocking position to automatically align reduced section 112 with slot 118 when breechblock 32 is actuated from the open to the closed position. When breechblock 32 reaches the closed position and shaft 64 is axially aligned with aperture 106, shaft 64 is freed to permit the forward actuation of firing pin 62 to the cocked position by spring 72.

Downward displacement of breechblock 32 past the open position is releasably prevented by a retainer 124 which is of inverted U-shape and which is fixed as by screw means to the rear end of the breechblock so as to straddle guard 88. Retainer 124- is fabricated from flat spring stock and is fixed to breechblock 32 at the bottom ends'of the arms so that the top of the retainer may be resiliently pulled back from the breechblock. Tabs 126 extend laterally outward from opposite sides of retainer 124 at the upper end thereof and such tabs contact corresponding stops 128, which extend rearwardly from breech housing 30, when breechblock 32 is in the open position.

When the top of retainer 124 is pulled rearwardly so that the tabs 126 are displaced clear of the stops .128, breechblock 32 is free to be displaced below the open position for disengagement of flanges 38 from grooves 40, whereupon casing 42 is free to be pulled rearwardly for disengagement of slots 52 from pin 50.

In FIG. 8 there is illustrated an alternate launcher 14' which is essentially the same as launcher 14 except that a breechblock 32 is integral with a casing 42 and is provided with arcuate flanges 38' which are concentric to pin 50 and which extend from the sides of the breechblock for sliding engagement with mating grooves 40 which are also concentric to such pin.

When a case 20 is to be loaded into launcher 14, firing 'pin'62 is manually pulled back past the cocked position block 32 is unlocked, the firing pin is releasably held in the cock position by sear portion 100.

Round 16 is then inserted into tube 28 to the position where rim 22 on case 20 contacts the rear end of the tube and breechblock 32 is swung to the closed position. When breechblock'32approaches :the closed position, angular sides 120 of segmental cuts contact chamfer 122 to earn firing pin 62"tothe' unlocking "position,- "whe reby reduced section 112 is displacedi'nto registry with slot 118 for passage therethrough to permitfirial displacement of breechblock 32 to the closed positio'nI The release of firing pin 62, after breechblock 32 is in closed position, permits the displacement-of .the firing pin to the, cockposition ready for release to discharge round 16, when trigger 94 and'safety device-96 are squeezed together, and the uninterrupted portion of shaft 64 is displaced into aperture 106'to lock the breechblock in the closed position.

From the foregoing, it is clearly apparent that there is provided herein a grenade launcher which is distinguished for its simplicity of design and ruggedness of construction; I

Although a particular embodiment of the invention has been described in detail herein, it 'is evident that many variations may be devised within the spirit and scope thereof and the following claims are intended to include such variations.

I claim:

1. An ammunition launcher for discharge of a round of ammunition, the launcher including a tube attachable to a firearm barrel and adapted for receiving the round for discharge, a breechblock, means for guiding said breechblock between an open and a closed position relative to 'said tube, a firing mechanism including a casing and a firing pin slidingly disposed therein, means for mounting said casing between said tube and said breechblock to provide means for pivotally mounting said breechblock to said tube for actuation between the open and closed positions, and cooperating means on said firing pin and said tube for releasably locking said breechblock in the closed position.

2. An ammunition launcher for discharge of a round of ammunition, the launcher including a tube attachable to afirearm barrel and adapted for receiving the round for discharge, a breech housing formed on the rear portion of said tube, a breechblock mounted in said breech housing for sliding displacement between an open and a closed position relative to said tube, a firing mechanism for discharging the round when said breechblock isin the closed position, said firing mechanism including a casing pivotally mounted at the front end to the front end of said tube and fixed at the rear end to said breechblock, a firing pin supported by said casing for axial displacement relative thereto, sear means for releasably blocking said firing pin in a cocked position after rearward displacement thereto, cooperatingmeans on said firing pin and said tube for locking said breechblock in the closed position and means for disengaging said firing pin from said tube to unlock said breechblock from the closed position when said firing pin is pulled back beyond the cocked position.

3. The ammunition launcher as defined in claim 2 wherein said sear means, a trigger and a safety lever are contained in said casing and said casing provides the means for displacing said breechblock between the open and closed positions. I k

, 4. The ammunition launcher as defined in claim 2 wherein said casing is provided with a longitudinal bore and a vertical opening which interrupts said bore and matingly receives a locking lug extending from said tube when said breechblock is in the closed position, said locking lug being provided with a longitudinal aperture therethrough. and a vertical slot to, provide entrance thereinto, said aperture having a diameter similar to that of said bore and being disposed for axial alignmenttherewith when said breechblock is in the closed position and said slot has a width less than the diameter of said aperture, and wherein said firing pin is provided with a cylindrical shaft which is slidingly received by said bore and is provided with a reduced section arranged for registry with said slot for passage therethrough when said firing pin is pulled back beyond the cocked position, whereby said breechblock is displaceable to the closed position when said firing pin is pulled back beyond the cocked position and is locked in the closed position when the firing pin is released to the cocked position.

5. The ammunition launcher as defined in claim 4 wherein said reduced section is formed by a pair of laterally spaced segmental cuts each of which is provided with an angular side disposed for camming contact with a chamfer on said locking lug to displace said firing pin for automatically registering said reduced section with said slot when said breechblock is moved to the closed position.

6. An ammunition launcher for discharge of a round of ammunition, the launcher including a tube attachable to a firearm barrel and adapted for receiving the round for discharge, a breech housing integrally formed at the rear portion of said tube, a breechblock for supporting the round for discharge, means for mounting said breechblock in said breech housing for vertical displacement between an open and a closed position relative to said tube, a firing mechanism including a casing pivotally mounted at the front end to the front end of said tube and pivotally mounted at the rear end to said breechblock, and means for mounting said casing between said tube and breechblock to provide means for manual actuation thereof between the open and closed positions.

7. An ammunition launcher for discharge of a round of ammunition, the launcher including a tube attachable to a firearm barrel and adapted for receiving the round for discharge, a breech housing integrally formed at the rear portion of said tube, a breechblock for supporting the round for discharge, means for mounting said breechblock in said breech housing for vertical displacement between an open and a closed position relative to said tube, a firing mechanism including a casing pivotally mounted at the front end to the front end of said tube, said breechblock being integrally formed on the rear end of said casing, and means for mounting said casing between said tube and breechblock to provide means for manual actuation thereof between the open and closed positions.

References Cited UNITED STATES PATENTS 2,480,328 8/1949 Johnston 891.7 2,483,421 10/1949 Kroeger et a1. 891.7 2,798,413 7/1957 Fowler 891.7

BENJAMIN A. BORCHELT, Primary Examiner. 

1. AN AMMUNITION LAUNCHER FOR DISCHARGE OF A ROUND OF AMMUNITION, THE LAUNCHER INCLUDING A TUBE ATTACHABLE TO A FIREARM BARREL AND ADAPTED FOR RECEIVING THE ROUND FOR DISCHARGE, A BREECHBLOCK, MEANS FOR GUIDING SAID BREECHBLOCK BETWEEN AN OPEN AND A CLOSED POSITION RELATIVE TO SAID TUBE, A FIRING MECHANISM INCLUDING A CASING AND A FIRING PIN SLIDINGLY DISPOSED THEREIN, MEANS FOR MOUNTING SAID CASING BETWEEN SAID TUBE AND SAID BREECHBLOCK TO PROVIDE MEANS FOR PIVOTALLY MOUNTING SAID BREECHBLOCK TO SAID TUBE FOR ACTUATION BETWEEN THE OPEN AND CLOSED POSITIONS, AND COOPERATING MEANS ON SAID FIRING PIN AND SAID TUBE FOR RELEASABLY LOCKING SAID BREECHBLOCK IN THE CLOSED POSITION. 